When Game of Thrones first debuted, Jaime Lannister (Nikolaj Coster-Waldau) was widely viewed as a sniveling, yet extremely handsome villainous character -- drawing comparisons to Shrek’s Prince Charming -- who did nothing more than set the entire series in motion by pushing a boy out of a window after he’d spied Jaime having sex with his sister, Cersei. “He was a bit of a douche,” Coster-Waldau admits to ET.

But Jaime soon evolved from the formidable Kingslayer into something more layered and complex: he lost a hand; befriended and eventually saved his enemy, Brienne of Tarth; and developed shades of morality that led him to question his sister’s motives to the point that he leaves King’s Landing. And by the end of season seven -- if not earlier -- he had become a fan favorite.

“In season three, you felt this shift in the way that audiences perceived the character,” Coster-Waldau explains. “They might have liked him as a character, but they didn’t like him as a person. But the nature of the show, you get to know someone more and more and it’s like, ‘OK, he’s having sex with his sister, but there’s more to this guy.’ And I think the fact that he left at the end of season seven, there was a sense of relief.”

In that evolution, the actor got more to do, especially in season seven, when he delivered some of his best work and finally earned an Emmy nomination for Outstanding Supporting Actor in a Drama Series. Fittingly, he’s one of the show’s four acting nominees this year, alongside his biggest scene partners, Peter Dinklage (Tyrion Lannister), Lena Headey (Cersei) and Dame Diana Rigg (Olenna Tyrell), with whom he shares one of the season’s best moments.

While nominated for episode four, “The Spoils of War,” which features some of the show’s biggest battle scenes yet, Coster-Waldau’s best work, perhaps, comes at the end of the episode prior, “The Queen’s Justice,” when Jaime carries out the execution of Olenna. In a moment of mercy, he offers her a quick, painless death by poison, which she takes right before confessing to killing Joffrey, catching Jaime completely off-guard.

“It was a great scene,” Coster-Waldau says, adding that Jaime “had to do what he had to do, but he did it with such grace. But of course, the beauty of the scene is that at the very end, she flips the power dynamic. It was very thrilling to be a part of Diana’s last scene on Thrones.”

Nikolaj Coster-Waldau with Diana Rigg in a scene from 'Game of Thrones.'

HBO

While the battle sequences are showy and breathtaking -- Jaime did charge straight at the mouth of a dragon in “The Spoils of War” -- it’s moments like Olenna’s last one that reveal more nuance and intrigue in each of the characters. In fact, when asked about moments from season seven that stand out the most to him, Coster-Waldau mentions the final scene he shares with Headey in the finale.

“We had seven years to build up to this moment where he finally says no to her. His whole life has been about trying to navigate around her and protect her and do whatever he could to do to be there for her. Now, suddenly, he can’t do what she wants him to do. She’s overstepped her boundaries, and clearly they have been stretching, but this time something snapped,” the actor explains of Jaime’s decision to finally break away from his sister. “Working with Lena has always been a joy.”

Of course, when speaking to Coster-Waldau about Jaime’s journey and evolution, it’s hard not to ask about what’s to come in the show’s final six episodes of season eight. Fearful of getting an “angry phone call” from execs at HBO, he won’t go into specifics about his character, but he does say it’s a relief to have survived to the last season, which they finished filming over the summer.

“I was talking to Lena about this before we both found out. I was going, ‘At this point, now that we’re so close, you just want to make it to the end,’” Coster-Waldau says. “If you had gone out in season three or four, it would have been fine. But now, we’re so close. It was definitely a relief to be a part of it.”

And with filming complete, Coster-Waldau and the entire cast and crew are in the midst of a series of long goodbyes that started on set with “hundreds of farewell dinners” and teary departures and will continue into promoting the final season and, perhaps, another Emmy ceremony.

“I’m really going to miss working on a scale and a level like we have for the past nine years,” Coster-Waldau says.

The 70th Primetime Emmy Awards, co-hosted by Saturday Night Live’s Colin Jost and Michael Che, will air live from the Microsoft Theater in Los Angeles on Monday, Sept. 17, starting at 8 p.m. ET/5 p.m. PT on NBC. Check out the full list of nominees and ET’s ongoing Emmy coverage here.